• Sometimes you can hit a block coming up with themes for a painting. Here are some quick ideas you can use to get started. They're just starting points, of course. You are the artist, so use, modify, improvise or augment the ideas to get what you are looking for.
  
  

Bouquet

• Get a large bouquet of flowers. Arrange it to your taste and set up your canvas. Turn the bouquet around and paint the back side, not the one you arranged. Renoir used to do this.
  
  

Improvisation

• Put your painting on the floor. Find three or four random small objects around the house. Close your eyes and toss them onto the painting. Outline them where they fall with pencil, and use them as a composition.
  
  

Collage 1

• Collect a dozen or so interesting photographs from magazines or other sources. Cut or tear them up into pieces and paste them onto a large piece of cardboard or poster board. Paint it.
  
  

Collage 2

• Instead of pasting the photographs onto cardboard, glue them directly onto your canvas. Paint directly over the collage in acrylic paint, painting over what you don't like and leaving or enhancing what you do like. Pay attention to transitions between painted areas and collage.
  
  

Self-Portrait

• The self-portrait is a time-honored theme for a painting. Set up a mirror in your studio. Use a dramatic light from one side if you wish. Sketch out your self-portrait in pencil on the canvas so you have a strong base from which to begin.
  
  

Geometric Abstraction

• Sketch a drawing for the painting using only triangles or only squares. Let them overlap or intersect. Pay attention to the negative space (the spaces created between the forms), and see if you can create interesting forms in this negative space. Do a painting based on the sketch, improvising with color as you go.
  
  

Color Harmony 1

• Find a landscape to paint. You can work outside or use a photograph. Paint the landscape, but use only the primary colors--red, yellow and blue--along with black and white paint. This will produce a dynamic color harmony.
  
  

Color Harmony 2

• Using the same landscape as for the prior painting, execute the landscape using only five analogous colors (colors that lie beside each other on the color wheel), along with black and white. Select five colors in a row from this list: red, red-orange, orange, yellow-orange, yellow, yellow-green, green, green-blue, blue, blue-purple, purple, purple-red. The analogous colors will produce a more tranquil color harmony.